From: Al Viro <viro@ZenIV.linux.org.uk>
To: Eric Dumazet <eric.dumazet@gmail.com>
Cc: Andrew Morton <akpm@linux-foundation.org>,
"linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
Dmitry Vyukov <dvyukov@google.com>,
Eric Dumazet <edumazet@google.com>,
linux-fsdevel@vger.kernel.org
Subject: Re: [PATCH] fs/file.c: __fget() and dup2() atomicity rules
Date: Mon, 29 Jun 2015 18:46:16 +0100 [thread overview]
Message-ID: <20150629174616.GZ17109@ZenIV.linux.org.uk> (raw)
In-Reply-To: <1435590630.4110.107.camel@edumazet-glaptop2.roam.corp.google.com>
On Mon, Jun 29, 2015 at 05:10:30PM +0200, Eric Dumazet wrote:
> From: Eric Dumazet <edumazet@google.com>
>
> __fget() makes sure a file refcount is not zero before
> taking a reference. It should also fetch again file pointer
> in order to respect dup2() atomicity requirements.
>
> It should either read a NULL pointer or a file on which
> a refcount can be taken.
Hmm... The problem is real, but I wonder if one could trigger a long
spin there...
next prev parent reply other threads:[~2015-06-29 17:46 UTC|newest]
Thread overview: 3+ messages / expand[flat|nested] mbox.gz Atom feed top
2015-06-29 15:10 [PATCH] fs/file.c: __fget() and dup2() atomicity rules Eric Dumazet
2015-06-29 17:46 ` Al Viro [this message]
2015-06-30 5:02 ` Eric Dumazet
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